I don't remember the exact model of the PowerSupply, but it's really good, kind of "Gamer" suppy.

lm_sensors doesn't detect anything in this mother, but I took these from the BIOS:

V+12 12.187

V+5 5.051

V3.3 3.266

VMEM 1.510

VProc 1.113

One more thing, I can't confirm, but I'm pretty sure that using an older bios (876), I had to unplug the machine for the card to appear. It changed to "every other boot" in version 888. Also version 888 changelog mentions something about "quad port" cards, but for windows.

Try to search for "Force Gen1" option in MB BIOS Setup, this will force PCIE v1.1 protocol to all 2.0 slots and likely solve detection troubles. Of course, videocard will be also affected, but if it is not top-level 'iron', you will loose really nothing in terms of performance.

Seems like this option isn`t available in Intel BIOSes, although other vendors (like ASUS) have it. May be this option still supported by BIOS, but hidden in Setup, Intel Integrator Toolkit utilities may bring it back to light by editing & reflashing BIOS, but this too much efforts for making buggy controller work.